1. Field
The present invention relates to a light emitting diode (LED) module and a lighting assembly, and more particularly, to an LED module and a lighting assembly, which employ a driver integrated circuit device.
2. Background
Light emitting diode (LED) lighting assemblies have been used in place of conventional incandescent bulbs and fluorescent lamps. An LED lighting assembly generally comprises an LED module having an LED mounted on a printed circuit board (PCB), a driver circuit unit for driving the LED, and a heat sink for dissipating heat generated from the LED.
The conventional driver circuit unit comprises an electrolytic capacitor for lowering a relatively high voltage such as household AC power to a voltage required for driving the LED, a converter for converting AC power into DC power, and the like. The electrolytic capacitor or the converter is individually mounted on the PCB together with the LED or is assembled in the lighting assembly by being spaced apart from the PCB. However, since the electrolytic capacitor or the converter has a relatively shorter lifespan than the LED, the electrolytic capacitor or the converter has influence on the lifespan of the lighting assembly, and causes a power loss due to the voltage drop.
A driver integrated circuit device having a driver circuit integrated in a single chip or package has been developed so as to solve the problem of the driver circuit unit.
FIG. 1 is a sectional view schematically showing a lighting assembly comprising a driver integrated circuit.
Referring to FIG. 1, the lighting assembly comprises a heat sink 11, a PCB 13, a light emitting device 15 and a driver integrated circuit device 17.
The light emitting device 15 and the driver integrated circuit 17 are mounted on a same surface of the PCB 13, and are electrically connected to each other through a wire in the PCB. Accordingly, when the lighting assembly is connected to an external power source, the light emitting device 15 is driven by a driver circuit of the driver integrated circuit device 17.
Meanwhile, the heat sink 11 is disposed on a bottom surface of the PCB 13 so as to dissipate heat generated from the light emitting device 15. A metal PCB, a metal core PCB or the like may be used as the PCB 13 so that the heat generated from the light emitting device 15 is well transferred to the heat sink 11.
As the driver integrated circuit device 17 is employed, the assembling process of the lighting assembly is simplified, and consequently, the cost is decreased. Further, as the heat sink 11 is employed, it is possible to prevent the light emitting device 15 and the driver integrated circuit device 17 from being damaged by heat.
However, when the light emitting device is used in the lighting assembly, a relatively high optical power is required, and therefore, a considerable amount of heat is generated from the light emitting device. As a result, a relatively large-sized heat sink 11 is required to dissipate the heat generated from the light emitting device. Accordingly, the size of the lighting assembly is relatively increased, and the manufacturing cost of the lighting assembly is increased.
Meanwhile, if the size of the heat sink 11 is decreased, the heat dissipation performance of the heat sink 11 is decreased. As a result, while the lighting assembly is used, the temperature of the PCB 13 is relatively increased, and therefore, the heat may be transferred from the PCB 13 to the driver integrated circuit device 17. Accordingly, the temperature of the driver integrated circuit device 17 is increased, and therefore, a malfunction of the driver integrated circuit 17 may be caused. Further, the driver integrated circuit device 17 is damaged by heat, and therefore, the lifespan of the lighting assembly may be decreased.